1 /*
2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions, and the following disclaimer,
10 * without modification, immediately at the beginning of the file.
11 * 2. The name of the author may not be used to endorse or promote products
12 * derived from this software without specific prior written permission.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
18 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: src/sys/i386/i386/busdma_machdep.c,v 1.94 2008/08/15 20:51:31 kmacy Exp $
27 */
28
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/malloc.h>
32 #include <sys/mbuf.h>
33 #include <sys/uio.h>
34 #include <sys/bus_dma.h>
35 #include <sys/kernel.h>
36 #include <sys/sysctl.h>
37 #include <sys/lock.h>
38
39 #include <sys/spinlock2.h>
40
41 #include <vm/vm.h>
42 #include <vm/vm_page.h>
43
44 /* XXX needed for to access pmap to convert per-proc virtual to physical */
45 #include <sys/proc.h>
46 #include <vm/vm_map.h>
47
48 #include <machine/md_var.h>
49 #include <machine/pmap.h>
50
51 #include <bus/cam/cam.h>
52 #include <bus/cam/cam_ccb.h>
53
54 #define MAX_BPAGES 1024
55
56 /*
57 * 16 x N declared on stack.
58 */
59 #define BUS_DMA_CACHE_SEGMENTS 8
60
61 struct bounce_zone;
62 struct bus_dmamap;
63
64 struct bus_dma_tag {
65 bus_size_t alignment;
66 bus_size_t boundary;
67 bus_addr_t lowaddr;
68 bus_addr_t highaddr;
69 bus_size_t maxsize;
70 u_int nsegments;
71 bus_size_t maxsegsz;
72 int flags;
73 int map_count;
74 bus_dma_segment_t *segments;
75 struct bounce_zone *bounce_zone;
76 struct spinlock spin;
77 };
78
79 /*
80 * bus_dma_tag private flags
81 */
82 #define BUS_DMA_BOUNCE_ALIGN BUS_DMA_BUS2
83 #define BUS_DMA_BOUNCE_LOWADDR BUS_DMA_BUS3
84 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
85
86 #define BUS_DMA_COULD_BOUNCE (BUS_DMA_BOUNCE_LOWADDR | BUS_DMA_BOUNCE_ALIGN)
87
88 #define BUS_DMAMEM_KMALLOC(dmat) \
89 ((dmat)->maxsize <= PAGE_SIZE && \
90 (dmat)->alignment <= PAGE_SIZE && \
91 (dmat)->lowaddr >= ptoa(Maxmem))
92
93 struct bounce_page {
94 vm_offset_t vaddr; /* kva of bounce buffer */
95 bus_addr_t busaddr; /* Physical address */
96 vm_offset_t datavaddr; /* kva of client data */
97 bus_size_t datacount; /* client data count */
98 STAILQ_ENTRY(bounce_page) links;
99 };
100
101 struct bounce_zone {
102 STAILQ_ENTRY(bounce_zone) links;
103 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
104 STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
105 struct spinlock spin;
106 int total_bpages;
107 int free_bpages;
108 int reserved_bpages;
109 int active_bpages;
110 int total_bounced;
111 int total_deferred;
112 int reserve_failed;
113 bus_size_t alignment;
114 bus_addr_t lowaddr;
115 char zoneid[8];
116 char lowaddrid[20];
117 struct sysctl_ctx_list sysctl_ctx;
118 struct sysctl_oid *sysctl_tree;
119 };
120
121 #define BZ_LOCK(bz) spin_lock(&(bz)->spin)
122 #define BZ_UNLOCK(bz) spin_unlock(&(bz)->spin)
123
124 static struct lwkt_token bounce_zone_tok =
125 LWKT_TOKEN_INITIALIZER(bounce_zone_token);
126 static int busdma_zonecount;
127 static STAILQ_HEAD(, bounce_zone) bounce_zone_list =
128 STAILQ_HEAD_INITIALIZER(bounce_zone_list);
129
130 static int busdma_priv_zonecount = -1;
131
132 int busdma_swi_pending;
133 static int total_bounce_pages;
134 static int max_bounce_pages = MAX_BPAGES;
135 static int bounce_alignment = 1; /* XXX temporary */
136
137 TUNABLE_INT("hw.busdma.max_bpages", &max_bounce_pages);
138 TUNABLE_INT("hw.busdma.bounce_alignment", &bounce_alignment);
139
140 struct bus_dmamap {
141 struct bp_list bpages;
142 int pagesneeded;
143 int pagesreserved;
144 bus_dma_tag_t dmat;
145 void *buf; /* unmapped buffer pointer */
146 bus_size_t buflen; /* unmapped buffer length */
147 bus_dmamap_callback_t *callback;
148 void *callback_arg;
149 STAILQ_ENTRY(bus_dmamap) links;
150 };
151
152 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist =
153 STAILQ_HEAD_INITIALIZER(bounce_map_callbacklist);
154 static struct spinlock bounce_map_list_spin =
155 SPINLOCK_INITIALIZER(&bounce_map_list_spin, "bounce_map_list_spin");
156
157 static struct bus_dmamap nobounce_dmamap;
158
159 static int alloc_bounce_zone(bus_dma_tag_t);
160 static int alloc_bounce_pages(bus_dma_tag_t, u_int, int);
161 static void free_bounce_pages_all(bus_dma_tag_t);
162 static void free_bounce_zone(bus_dma_tag_t);
163 static int reserve_bounce_pages(bus_dma_tag_t, bus_dmamap_t, int);
164 static void return_bounce_pages(bus_dma_tag_t, bus_dmamap_t);
165 static bus_addr_t add_bounce_page(bus_dma_tag_t, bus_dmamap_t,
166 vm_offset_t, bus_size_t *);
167 static void free_bounce_page(bus_dma_tag_t, struct bounce_page *);
168
169 static bus_dmamap_t get_map_waiting(bus_dma_tag_t);
170 static void add_map_callback(bus_dmamap_t);
171
172 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
173 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bounce_pages,
174 0, "Total bounce pages");
175 SYSCTL_INT(_hw_busdma, OID_AUTO, max_bpages, CTLFLAG_RD, &max_bounce_pages,
176 0, "Max bounce pages per bounce zone");
177 SYSCTL_INT(_hw_busdma, OID_AUTO, bounce_alignment, CTLFLAG_RD,
178 &bounce_alignment, 0, "Obey alignment constraint");
179
180
181 /*
182 * Returns true if the address falls within the tag's exclusion window, or
183 * fails to meet its alignment requirements.
184 */
185 static __inline int
addr_needs_bounce(bus_dma_tag_t dmat,bus_addr_t paddr)186 addr_needs_bounce(bus_dma_tag_t dmat, bus_addr_t paddr)
187 {
188 if ((paddr > dmat->lowaddr && paddr <= dmat->highaddr) ||
189 (bounce_alignment && (paddr & (dmat->alignment - 1)) != 0))
190 return (1);
191
192 return (0);
193 }
194
195 static __inline
196 bus_dma_segment_t *
bus_dma_tag_lock(bus_dma_tag_t tag,bus_dma_segment_t * cache)197 bus_dma_tag_lock(bus_dma_tag_t tag, bus_dma_segment_t *cache)
198 {
199 if (tag->flags & BUS_DMA_PROTECTED)
200 return(tag->segments);
201
202 if (tag->nsegments <= BUS_DMA_CACHE_SEGMENTS)
203 return(cache);
204 spin_lock(&tag->spin);
205 return(tag->segments);
206 }
207
208 static __inline
209 void
bus_dma_tag_unlock(bus_dma_tag_t tag)210 bus_dma_tag_unlock(bus_dma_tag_t tag)
211 {
212 if (tag->flags & BUS_DMA_PROTECTED)
213 return;
214
215 if (tag->nsegments > BUS_DMA_CACHE_SEGMENTS)
216 spin_unlock(&tag->spin);
217 }
218
219 /*
220 * Allocate a device specific dma_tag.
221 */
222 int
bus_dma_tag_create(bus_dma_tag_t parent,bus_size_t alignment,bus_size_t boundary,bus_addr_t lowaddr,bus_addr_t highaddr,bus_size_t maxsize,int nsegments,bus_size_t maxsegsz,int flags,bus_dma_tag_t * dmat)223 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
224 bus_size_t boundary, bus_addr_t lowaddr,
225 bus_addr_t highaddr, bus_size_t maxsize, int nsegments,
226 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat)
227 {
228 bus_dma_tag_t newtag;
229 int error = 0;
230
231 /*
232 * Sanity checks
233 */
234
235 if (alignment == 0)
236 alignment = 1;
237 if (alignment & (alignment - 1))
238 panic("alignment must be power of 2");
239
240 if (boundary != 0) {
241 if (boundary & (boundary - 1))
242 panic("boundary must be power of 2");
243 if (boundary < maxsegsz) {
244 kprintf("boundary < maxsegsz:\n");
245 print_backtrace(-1);
246 maxsegsz = boundary;
247 }
248 }
249
250 /* Return a NULL tag on failure */
251 *dmat = NULL;
252
253 newtag = kmalloc(sizeof(*newtag), M_DEVBUF, M_INTWAIT | M_ZERO);
254
255 spin_init(&newtag->spin, "busdmacreate");
256 newtag->alignment = alignment;
257 newtag->boundary = boundary;
258 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
259 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
260 newtag->maxsize = maxsize;
261 newtag->nsegments = nsegments;
262 newtag->maxsegsz = maxsegsz;
263 newtag->flags = flags;
264 newtag->map_count = 0;
265 newtag->segments = NULL;
266 newtag->bounce_zone = NULL;
267
268 /* Take into account any restrictions imposed by our parent tag */
269 if (parent != NULL) {
270 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
271 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
272
273 if (newtag->boundary == 0) {
274 newtag->boundary = parent->boundary;
275 } else if (parent->boundary != 0) {
276 newtag->boundary = MIN(parent->boundary,
277 newtag->boundary);
278 }
279
280 #ifdef notyet
281 newtag->alignment = MAX(parent->alignment, newtag->alignment);
282 #endif
283
284 }
285
286 if (newtag->lowaddr < ptoa(Maxmem))
287 newtag->flags |= BUS_DMA_BOUNCE_LOWADDR;
288 if (bounce_alignment && newtag->alignment > 1 &&
289 !(newtag->flags & BUS_DMA_ALIGNED))
290 newtag->flags |= BUS_DMA_BOUNCE_ALIGN;
291
292 if ((newtag->flags & BUS_DMA_COULD_BOUNCE) &&
293 (flags & BUS_DMA_ALLOCNOW) != 0) {
294 struct bounce_zone *bz;
295
296 /* Must bounce */
297
298 error = alloc_bounce_zone(newtag);
299 if (error)
300 goto back;
301 bz = newtag->bounce_zone;
302
303 if ((newtag->flags & BUS_DMA_ALLOCALL) == 0 &&
304 ptoa(bz->total_bpages) < maxsize) {
305 int pages;
306
307 if (flags & BUS_DMA_ONEBPAGE) {
308 pages = 1;
309 } else {
310 pages = atop(round_page(maxsize)) -
311 bz->total_bpages;
312 pages = MAX(pages, 1);
313 }
314
315 /* Add pages to our bounce pool */
316 if (alloc_bounce_pages(newtag, pages, flags) < pages)
317 error = ENOMEM;
318
319 /* Performed initial allocation */
320 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
321 }
322 }
323 back:
324 if (error) {
325 free_bounce_zone(newtag);
326 kfree(newtag, M_DEVBUF);
327 } else {
328 *dmat = newtag;
329 }
330 return error;
331 }
332
333 int
bus_dma_tag_destroy(bus_dma_tag_t dmat)334 bus_dma_tag_destroy(bus_dma_tag_t dmat)
335 {
336 if (dmat != NULL) {
337 if (dmat->map_count != 0)
338 return (EBUSY);
339
340 free_bounce_zone(dmat);
341 if (dmat->segments != NULL)
342 kfree(dmat->segments, M_DEVBUF);
343 kfree(dmat, M_DEVBUF);
344 }
345 return (0);
346 }
347
348 bus_size_t
bus_dma_tag_getmaxsize(bus_dma_tag_t tag)349 bus_dma_tag_getmaxsize(bus_dma_tag_t tag)
350 {
351 return(tag->maxsize);
352 }
353
354 /*
355 * Allocate a handle for mapping from kva/uva/physical
356 * address space into bus device space.
357 */
358 int
bus_dmamap_create(bus_dma_tag_t dmat,int flags,bus_dmamap_t * mapp)359 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
360 {
361 int error;
362
363 error = 0;
364
365 if (dmat->segments == NULL) {
366 KKASSERT(dmat->nsegments && dmat->nsegments < 16384);
367 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
368 dmat->nsegments, M_DEVBUF, M_INTWAIT);
369 }
370
371 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
372 struct bounce_zone *bz;
373 int maxpages;
374
375 /* Must bounce */
376
377 if (dmat->bounce_zone == NULL) {
378 error = alloc_bounce_zone(dmat);
379 if (error)
380 return error;
381 }
382 bz = dmat->bounce_zone;
383
384 *mapp = kmalloc(sizeof(**mapp), M_DEVBUF, M_INTWAIT | M_ZERO);
385
386 /* Initialize the new map */
387 STAILQ_INIT(&((*mapp)->bpages));
388
389 /*
390 * Attempt to add pages to our pool on a per-instance
391 * basis up to a sane limit.
392 */
393 if (dmat->flags & BUS_DMA_ALLOCALL) {
394 maxpages = Maxmem - atop(dmat->lowaddr);
395 } else if (dmat->flags & BUS_DMA_BOUNCE_ALIGN) {
396 maxpages = max_bounce_pages;
397 } else {
398 maxpages = MIN(max_bounce_pages,
399 Maxmem - atop(dmat->lowaddr));
400 }
401 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0 ||
402 (dmat->map_count > 0 && bz->total_bpages < maxpages)) {
403 int pages;
404
405 if (flags & BUS_DMA_ONEBPAGE) {
406 pages = 1;
407 } else {
408 pages = atop(round_page(dmat->maxsize));
409 pages = MIN(maxpages - bz->total_bpages, pages);
410 pages = MAX(pages, 1);
411 }
412 if (alloc_bounce_pages(dmat, pages, flags) < pages)
413 error = ENOMEM;
414
415 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
416 if (!error &&
417 (dmat->flags & BUS_DMA_ALLOCALL) == 0)
418 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
419 } else {
420 error = 0;
421 }
422 }
423 } else {
424 *mapp = NULL;
425 }
426 if (!error) {
427 dmat->map_count++;
428 } else {
429 kfree(*mapp, M_DEVBUF);
430 *mapp = NULL;
431 }
432 return error;
433 }
434
435 /*
436 * Destroy a handle for mapping from kva/uva/physical
437 * address space into bus device space.
438 */
439 int
bus_dmamap_destroy(bus_dma_tag_t dmat,bus_dmamap_t map)440 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
441 {
442 if (map != NULL && map != (void *)-1) {
443 if (STAILQ_FIRST(&map->bpages) != NULL)
444 return (EBUSY);
445 kfree(map, M_DEVBUF);
446 }
447 dmat->map_count--;
448 return (0);
449 }
450
451 static __inline bus_size_t
check_kmalloc(bus_dma_tag_t dmat,const void * vaddr0,int verify)452 check_kmalloc(bus_dma_tag_t dmat, const void *vaddr0, int verify)
453 {
454 bus_size_t maxsize = 0;
455 uintptr_t vaddr = (uintptr_t)vaddr0;
456
457 if ((vaddr ^ (vaddr + dmat->maxsize - 1)) & ~PAGE_MASK) {
458 if (verify)
459 panic("boundary check failed\n");
460 maxsize = dmat->maxsize;
461 }
462 if (vaddr & (dmat->alignment - 1)) {
463 if (verify)
464 panic("alignment check failed\n");
465 if (dmat->maxsize < dmat->alignment)
466 maxsize = dmat->alignment;
467 else
468 maxsize = dmat->maxsize;
469 }
470 return maxsize;
471 }
472
473 /*
474 * Allocate a piece of memory that can be efficiently mapped into
475 * bus device space based on the constraints lited in the dma tag.
476 *
477 * Use *mapp to record whether we were able to use kmalloc()
478 * or whether we had to use contigmalloc().
479 */
480 int
bus_dmamem_alloc(bus_dma_tag_t dmat,void ** vaddr,int flags,bus_dmamap_t * mapp)481 bus_dmamem_alloc(bus_dma_tag_t dmat, void **vaddr, int flags,
482 bus_dmamap_t *mapp)
483 {
484 vm_memattr_t attr;
485 int mflags;
486
487 /* If we succeed, no mapping/bouncing will be required */
488 *mapp = NULL;
489
490 if (dmat->segments == NULL) {
491 KKASSERT(dmat->nsegments < 16384);
492 dmat->segments = kmalloc(sizeof(bus_dma_segment_t) *
493 dmat->nsegments, M_DEVBUF, M_INTWAIT);
494 }
495
496 if (flags & BUS_DMA_NOWAIT)
497 mflags = M_NOWAIT;
498 else
499 mflags = M_WAITOK;
500 if (flags & BUS_DMA_ZERO)
501 mflags |= M_ZERO;
502 if (flags & BUS_DMA_NOCACHE)
503 attr = VM_MEMATTR_UNCACHEABLE;
504 else
505 attr = VM_MEMATTR_DEFAULT;
506
507 /* XXX must alloc with correct mem attribute here */
508 if (BUS_DMAMEM_KMALLOC(dmat) && attr == VM_MEMATTR_DEFAULT) {
509 bus_size_t maxsize;
510
511 *vaddr = kmalloc(dmat->maxsize, M_DEVBUF, mflags);
512
513 /*
514 * XXX
515 * Check whether the allocation
516 * - crossed a page boundary
517 * - was not aligned
518 * Retry with power-of-2 alignment in the above cases.
519 */
520 maxsize = check_kmalloc(dmat, *vaddr, 0);
521 if (maxsize) {
522 kfree(*vaddr, M_DEVBUF);
523 *vaddr = kmalloc(maxsize, M_DEVBUF,
524 mflags | M_POWEROF2);
525 check_kmalloc(dmat, *vaddr, 1);
526 }
527 } else {
528 /*
529 * XXX Use Contigmalloc until it is merged into this facility
530 * and handles multi-seg allocations. Nobody is doing
531 * multi-seg allocations yet though.
532 */
533 *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
534 0ul, dmat->lowaddr,
535 dmat->alignment, dmat->boundary);
536 *mapp = (void *)-1;
537 }
538 if (*vaddr == NULL)
539 return (ENOMEM);
540
541 if (attr != VM_MEMATTR_DEFAULT) {
542 pmap_change_attr((vm_offset_t)(*vaddr),
543 dmat->maxsize / PAGE_SIZE, attr);
544 }
545 return (0);
546 }
547
548 /*
549 * Free a piece of memory and it's allociated dmamap, that was allocated
550 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
551 */
552 void
bus_dmamem_free(bus_dma_tag_t dmat,void * vaddr,bus_dmamap_t map)553 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
554 {
555 /*
556 * dmamem does not need to be bounced, so the map should be
557 * NULL
558 */
559 if (map != NULL && map != (void *)-1)
560 panic("bus_dmamem_free: Invalid map freed");
561 if (map == NULL)
562 kfree(vaddr, M_DEVBUF);
563 else
564 contigfree(vaddr, dmat->maxsize, M_DEVBUF);
565 }
566
567 static __inline vm_paddr_t
_bus_dma_extract(pmap_t pmap,vm_offset_t vaddr)568 _bus_dma_extract(pmap_t pmap, vm_offset_t vaddr)
569 {
570 if (pmap)
571 return pmap_extract(pmap, vaddr, NULL);
572 else
573 return pmap_kextract(vaddr);
574 }
575
576 /*
577 * Utility function to load a linear buffer. lastaddrp holds state
578 * between invocations (for multiple-buffer loads). segp contains
579 * the segment following the starting one on entrace, and the ending
580 * segment on exit. first indicates if this is the first invocation
581 * of this function.
582 */
583 static int
_bus_dmamap_load_buffer(bus_dma_tag_t dmat,bus_dmamap_t map,void * buf,bus_size_t buflen,bus_dma_segment_t * segments,int nsegments,pmap_t pmap,int flags,vm_paddr_t * lastpaddrp,int * segp,int first)584 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
585 bus_dmamap_t map,
586 void *buf, bus_size_t buflen,
587 bus_dma_segment_t *segments,
588 int nsegments,
589 pmap_t pmap,
590 int flags,
591 vm_paddr_t *lastpaddrp,
592 int *segp,
593 int first)
594 {
595 vm_offset_t vaddr;
596 vm_paddr_t paddr, nextpaddr;
597 bus_dma_segment_t *sg;
598 bus_addr_t bmask;
599 int seg, error = 0;
600
601 if (map == NULL || map == (void *)-1)
602 map = &nobounce_dmamap;
603
604 #ifdef INVARIANTS
605 if (dmat->flags & BUS_DMA_ALIGNED)
606 KKASSERT(((uintptr_t)buf & (dmat->alignment - 1)) == 0);
607 #endif
608
609 /*
610 * If we are being called during a callback, pagesneeded will
611 * be non-zero, so we can avoid doing the work twice.
612 */
613 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) &&
614 map != &nobounce_dmamap && map->pagesneeded == 0) {
615 vm_offset_t vendaddr;
616
617 /*
618 * Count the number of bounce pages
619 * needed in order to complete this transfer
620 */
621 vaddr = (vm_offset_t)buf;
622 vendaddr = (vm_offset_t)buf + buflen;
623
624 while (vaddr < vendaddr) {
625 paddr = _bus_dma_extract(pmap, vaddr);
626 if (addr_needs_bounce(dmat, paddr))
627 map->pagesneeded++;
628 vaddr += (PAGE_SIZE - (vaddr & PAGE_MASK));
629 }
630 }
631
632 /* Reserve Necessary Bounce Pages */
633 if (map->pagesneeded != 0) {
634 struct bounce_zone *bz;
635
636 bz = dmat->bounce_zone;
637 BZ_LOCK(bz);
638 if (flags & BUS_DMA_NOWAIT) {
639 if (reserve_bounce_pages(dmat, map, 0) != 0) {
640 BZ_UNLOCK(bz);
641 error = ENOMEM;
642 goto free_bounce;
643 }
644 } else {
645 if (reserve_bounce_pages(dmat, map, 1) != 0) {
646 /* Queue us for resources */
647 map->dmat = dmat;
648 map->buf = buf;
649 map->buflen = buflen;
650
651 STAILQ_INSERT_TAIL(
652 &dmat->bounce_zone->bounce_map_waitinglist,
653 map, links);
654 BZ_UNLOCK(bz);
655
656 return (EINPROGRESS);
657 }
658 }
659 BZ_UNLOCK(bz);
660 }
661
662 KKASSERT(*segp >= 1 && *segp <= nsegments);
663 seg = *segp;
664 sg = &segments[seg - 1];
665
666 vaddr = (vm_offset_t)buf;
667 nextpaddr = *lastpaddrp;
668 bmask = ~(dmat->boundary - 1); /* note: will be 0 if boundary is 0 */
669
670 /* force at least one segment */
671 do {
672 bus_size_t size;
673
674 /*
675 * Per-page main loop
676 */
677 paddr = _bus_dma_extract(pmap, vaddr);
678 size = PAGE_SIZE - (paddr & PAGE_MASK);
679 if (size > buflen)
680 size = buflen;
681 if (map->pagesneeded != 0 && addr_needs_bounce(dmat, paddr)) {
682 /*
683 * NOTE: paddr may have different in-page offset,
684 * unless BUS_DMA_KEEP_PG_OFFSET is set.
685 */
686 paddr = add_bounce_page(dmat, map, vaddr, &size);
687 }
688
689 /*
690 * Fill in the bus_dma_segment
691 */
692 if (first) {
693 sg->ds_addr = paddr;
694 sg->ds_len = size;
695 first = 0;
696 } else if (paddr == nextpaddr) {
697 sg->ds_len += size;
698 } else {
699 sg++;
700 seg++;
701 if (seg > nsegments)
702 break;
703 sg->ds_addr = paddr;
704 sg->ds_len = size;
705 }
706 nextpaddr = paddr + size;
707
708 /*
709 * Handle maxsegsz and boundary issues with a nested loop
710 */
711 for (;;) {
712 bus_size_t tmpsize;
713
714 /*
715 * Limit to the boundary and maximum segment size
716 */
717 if (((nextpaddr - 1) ^ sg->ds_addr) & bmask) {
718 tmpsize = dmat->boundary -
719 (sg->ds_addr & ~bmask);
720 if (tmpsize > dmat->maxsegsz)
721 tmpsize = dmat->maxsegsz;
722 KKASSERT(tmpsize < sg->ds_len);
723 } else if (sg->ds_len > dmat->maxsegsz) {
724 tmpsize = dmat->maxsegsz;
725 } else {
726 break;
727 }
728
729 /*
730 * Futz, split the data into a new segment.
731 */
732 if (seg >= nsegments)
733 goto fail;
734 sg[1].ds_len = sg[0].ds_len - tmpsize;
735 sg[1].ds_addr = sg[0].ds_addr + tmpsize;
736 sg[0].ds_len = tmpsize;
737 sg++;
738 seg++;
739 }
740
741 /*
742 * Adjust for loop
743 */
744 buflen -= size;
745 vaddr += size;
746 } while (buflen > 0);
747 fail:
748 if (buflen != 0)
749 error = EFBIG;
750
751 *segp = seg;
752 *lastpaddrp = nextpaddr;
753
754 free_bounce:
755 if (error && (dmat->flags & BUS_DMA_COULD_BOUNCE) &&
756 map != &nobounce_dmamap) {
757 _bus_dmamap_unload(dmat, map);
758 return_bounce_pages(dmat, map);
759 }
760 return error;
761 }
762
763 /*
764 * Map the buffer buf into bus space using the dmamap map.
765 */
766 int
bus_dmamap_load(bus_dma_tag_t dmat,bus_dmamap_t map,void * buf,bus_size_t buflen,bus_dmamap_callback_t * callback,void * callback_arg,int flags)767 bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
768 bus_size_t buflen, bus_dmamap_callback_t *callback,
769 void *callback_arg, int flags)
770 {
771 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
772 bus_dma_segment_t *segments;
773 vm_paddr_t lastaddr = 0;
774 int error, nsegs = 1;
775
776 if (map != NULL && map != (void *)-1) {
777 /*
778 * XXX
779 * Follow old semantics. Once all of the callers are fixed,
780 * we should get rid of these internal flag "adjustment".
781 */
782 flags &= ~BUS_DMA_NOWAIT;
783 flags |= BUS_DMA_WAITOK;
784
785 map->callback = callback;
786 map->callback_arg = callback_arg;
787 }
788
789 segments = bus_dma_tag_lock(dmat, cache_segments);
790 error = _bus_dmamap_load_buffer(dmat, map, buf, buflen,
791 segments, dmat->nsegments,
792 NULL, flags, &lastaddr, &nsegs, 1);
793 if (error == EINPROGRESS) {
794 KKASSERT((dmat->flags &
795 (BUS_DMA_PRIVBZONE | BUS_DMA_ALLOCALL)) !=
796 (BUS_DMA_PRIVBZONE | BUS_DMA_ALLOCALL));
797
798 if (dmat->flags & BUS_DMA_PROTECTED)
799 panic("protected dmamap callback will be defered");
800
801 bus_dma_tag_unlock(dmat);
802 return error;
803 }
804 callback(callback_arg, segments, nsegs, error);
805 bus_dma_tag_unlock(dmat);
806 return 0;
807 }
808
809 /*
810 * Like _bus_dmamap_load(), but for ccb.
811 */
812 int
bus_dmamap_load_ccb(bus_dma_tag_t dmat,bus_dmamap_t map,union ccb * ccb,bus_dmamap_callback_t * callback,void * callback_arg,int flags)813 bus_dmamap_load_ccb(bus_dma_tag_t dmat, bus_dmamap_t map, union ccb *ccb,
814 bus_dmamap_callback_t *callback, void *callback_arg, int flags)
815 {
816 const struct ccb_scsiio *csio;
817 struct ccb_hdr *ccb_h;
818
819 ccb_h = &ccb->ccb_h;
820 KASSERT(ccb_h->func_code == XPT_SCSI_IO ||
821 ccb_h->func_code == XPT_CONT_TARGET_IO,
822 ("invalid ccb func_code %u", ccb_h->func_code));
823 if ((ccb_h->flags & CAM_DIR_MASK) == CAM_DIR_NONE) {
824 callback(callback_arg, NULL, 0, 0);
825 return 0;
826 }
827 csio = &ccb->csio;
828
829 return (bus_dmamap_load(dmat, map, csio->data_ptr, csio->dxfer_len,
830 callback, callback_arg, flags));
831 }
832
833 /*
834 * Like _bus_dmamap_load(), but for mbufs.
835 */
836 int
bus_dmamap_load_mbuf(bus_dma_tag_t dmat,bus_dmamap_t map,struct mbuf * m0,bus_dmamap_callback2_t * callback,void * callback_arg,int flags)837 bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map,
838 struct mbuf *m0,
839 bus_dmamap_callback2_t *callback, void *callback_arg,
840 int flags)
841 {
842 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
843 bus_dma_segment_t *segments;
844 int nsegs, error;
845
846 /*
847 * XXX
848 * Follow old semantics. Once all of the callers are fixed,
849 * we should get rid of these internal flag "adjustment".
850 */
851 flags &= ~BUS_DMA_WAITOK;
852 flags |= BUS_DMA_NOWAIT;
853
854 segments = bus_dma_tag_lock(dmat, cache_segments);
855 error = bus_dmamap_load_mbuf_segment(dmat, map, m0,
856 segments, dmat->nsegments, &nsegs, flags);
857 if (error) {
858 /* force "no valid mappings" in callback */
859 callback(callback_arg, segments, 0,
860 0, error);
861 } else {
862 callback(callback_arg, segments, nsegs,
863 m0->m_pkthdr.len, error);
864 }
865 bus_dma_tag_unlock(dmat);
866 return error;
867 }
868
869 int
bus_dmamap_load_mbuf_segment(bus_dma_tag_t dmat,bus_dmamap_t map,struct mbuf * m0,bus_dma_segment_t * segs,int maxsegs,int * nsegs,int flags)870 bus_dmamap_load_mbuf_segment(bus_dma_tag_t dmat, bus_dmamap_t map,
871 struct mbuf *m0,
872 bus_dma_segment_t *segs, int maxsegs,
873 int *nsegs, int flags)
874 {
875 int error;
876
877 M_ASSERTPKTHDR(m0);
878
879 KASSERT(maxsegs >= 1, ("invalid maxsegs %d", maxsegs));
880 KASSERT(maxsegs <= dmat->nsegments,
881 ("%d too many segments, dmat only supports %d segments",
882 maxsegs, dmat->nsegments));
883 KASSERT(flags & BUS_DMA_NOWAIT,
884 ("only BUS_DMA_NOWAIT is supported"));
885
886 if (m0->m_pkthdr.len <= dmat->maxsize) {
887 int first = 1;
888 vm_paddr_t lastaddr = 0;
889 struct mbuf *m;
890
891 *nsegs = 1;
892 error = 0;
893 for (m = m0; m != NULL && error == 0; m = m->m_next) {
894 if (m->m_len == 0)
895 continue;
896
897 error = _bus_dmamap_load_buffer(dmat, map,
898 m->m_data, m->m_len,
899 segs, maxsegs,
900 NULL, flags, &lastaddr,
901 nsegs, first);
902 if (error == ENOMEM && !first) {
903 /*
904 * Out of bounce pages due to too many
905 * fragments in the mbuf chain; return
906 * EFBIG instead.
907 */
908 error = EFBIG;
909 break;
910 }
911 first = 0;
912 }
913 #ifdef INVARIANTS
914 if (!error)
915 KKASSERT(*nsegs <= maxsegs && *nsegs >= 1);
916 #endif
917 } else {
918 *nsegs = 0;
919 error = EINVAL;
920 }
921 KKASSERT(error != EINPROGRESS);
922 return error;
923 }
924
925 /*
926 * Like _bus_dmamap_load(), but for uios.
927 */
928 int
bus_dmamap_load_uio(bus_dma_tag_t dmat,bus_dmamap_t map,struct uio * uio,bus_dmamap_callback2_t * callback,void * callback_arg,int flags)929 bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map,
930 struct uio *uio,
931 bus_dmamap_callback2_t *callback, void *callback_arg,
932 int flags)
933 {
934 vm_paddr_t lastaddr;
935 int nsegs, error, first, i;
936 bus_size_t resid;
937 struct iovec *iov;
938 pmap_t pmap;
939 bus_dma_segment_t cache_segments[BUS_DMA_CACHE_SEGMENTS];
940 bus_dma_segment_t *segments;
941 bus_dma_segment_t *segs;
942 int nsegs_left;
943
944 if (dmat->nsegments <= BUS_DMA_CACHE_SEGMENTS)
945 segments = cache_segments;
946 else
947 segments = kmalloc(sizeof(bus_dma_segment_t) * dmat->nsegments,
948 M_DEVBUF, M_WAITOK | M_ZERO);
949
950 /*
951 * XXX
952 * Follow old semantics. Once all of the callers are fixed,
953 * we should get rid of these internal flag "adjustment".
954 */
955 flags &= ~BUS_DMA_WAITOK;
956 flags |= BUS_DMA_NOWAIT;
957
958 resid = (bus_size_t)uio->uio_resid;
959 iov = uio->uio_iov;
960
961 segs = segments;
962 nsegs_left = dmat->nsegments;
963
964 if (uio->uio_segflg == UIO_USERSPACE) {
965 struct thread *td;
966
967 td = uio->uio_td;
968 KASSERT(td != NULL && td->td_proc != NULL,
969 ("bus_dmamap_load_uio: USERSPACE but no proc"));
970 pmap = vmspace_pmap(td->td_proc->p_vmspace);
971 } else {
972 pmap = NULL;
973 }
974
975 error = 0;
976 nsegs = 1;
977 first = 1;
978 lastaddr = 0;
979 for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
980 /*
981 * Now at the first iovec to load. Load each iovec
982 * until we have exhausted the residual count.
983 */
984 bus_size_t minlen =
985 resid < iov[i].iov_len ? resid : iov[i].iov_len;
986 caddr_t addr = (caddr_t) iov[i].iov_base;
987
988 error = _bus_dmamap_load_buffer(dmat, map, addr, minlen,
989 segs, nsegs_left,
990 pmap, flags, &lastaddr, &nsegs, first);
991 first = 0;
992
993 resid -= minlen;
994 if (error == 0) {
995 nsegs_left -= nsegs;
996 segs += nsegs;
997 }
998 }
999
1000 /*
1001 * Minimum one DMA segment, even if 0-length buffer.
1002 */
1003 if (nsegs_left == dmat->nsegments)
1004 --nsegs_left;
1005
1006 if (error) {
1007 /* force "no valid mappings" in callback */
1008 callback(callback_arg, segments, 0,
1009 0, error);
1010 } else {
1011 callback(callback_arg, segments, dmat->nsegments - nsegs_left,
1012 (bus_size_t)uio->uio_resid, error);
1013 }
1014 if (dmat->nsegments > BUS_DMA_CACHE_SEGMENTS)
1015 kfree(segments, M_DEVBUF);
1016 return error;
1017 }
1018
1019 /*
1020 * Release the mapping held by map.
1021 */
1022 void
_bus_dmamap_unload(bus_dma_tag_t dmat,bus_dmamap_t map)1023 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
1024 {
1025 struct bounce_page *bpage;
1026
1027 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
1028 STAILQ_REMOVE_HEAD(&map->bpages, links);
1029 free_bounce_page(dmat, bpage);
1030 }
1031 }
1032
1033 void
_bus_dmamap_sync(bus_dma_tag_t dmat,bus_dmamap_t map,bus_dmasync_op_t op)1034 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
1035 {
1036 struct bounce_page *bpage;
1037
1038 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
1039 /*
1040 * Handle data bouncing. We might also
1041 * want to add support for invalidating
1042 * the caches on broken hardware
1043 */
1044 if (op & BUS_DMASYNC_PREWRITE) {
1045 while (bpage != NULL) {
1046 bcopy((void *)bpage->datavaddr,
1047 (void *)bpage->vaddr,
1048 bpage->datacount);
1049 bpage = STAILQ_NEXT(bpage, links);
1050 }
1051 cpu_sfence();
1052 dmat->bounce_zone->total_bounced++;
1053 }
1054 if (op & BUS_DMASYNC_POSTREAD) {
1055 cpu_lfence();
1056 while (bpage != NULL) {
1057 bcopy((void *)bpage->vaddr,
1058 (void *)bpage->datavaddr,
1059 bpage->datacount);
1060 bpage = STAILQ_NEXT(bpage, links);
1061 }
1062 dmat->bounce_zone->total_bounced++;
1063 }
1064 /* BUS_DMASYNC_PREREAD - no operation on intel */
1065 /* BUS_DMASYNC_POSTWRITE - no operation on intel */
1066 }
1067 }
1068
1069 static int
alloc_bounce_zone(bus_dma_tag_t dmat)1070 alloc_bounce_zone(bus_dma_tag_t dmat)
1071 {
1072 struct bounce_zone *bz, *new_bz;
1073
1074 KASSERT(dmat->bounce_zone == NULL,
1075 ("bounce zone was already assigned"));
1076
1077 new_bz = kmalloc(sizeof(*new_bz), M_DEVBUF, M_INTWAIT | M_ZERO);
1078
1079 lwkt_gettoken(&bounce_zone_tok);
1080
1081 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0) {
1082 /*
1083 * For shared bounce zone, check to see
1084 * if we already have a suitable zone
1085 */
1086 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
1087 if (dmat->alignment <= bz->alignment &&
1088 dmat->lowaddr >= bz->lowaddr) {
1089 lwkt_reltoken(&bounce_zone_tok);
1090
1091 dmat->bounce_zone = bz;
1092 kfree(new_bz, M_DEVBUF);
1093 return 0;
1094 }
1095 }
1096 }
1097 bz = new_bz;
1098
1099 spin_init(&bz->spin, "allocbouncezone");
1100 STAILQ_INIT(&bz->bounce_page_list);
1101 STAILQ_INIT(&bz->bounce_map_waitinglist);
1102 bz->free_bpages = 0;
1103 bz->reserved_bpages = 0;
1104 bz->active_bpages = 0;
1105 bz->lowaddr = dmat->lowaddr;
1106 bz->alignment = round_page(dmat->alignment);
1107 ksnprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
1108
1109 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0) {
1110 ksnprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
1111 busdma_zonecount++;
1112 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
1113 } else {
1114 ksnprintf(bz->zoneid, 8, "zone%d", busdma_priv_zonecount);
1115 busdma_priv_zonecount--;
1116 }
1117
1118 lwkt_reltoken(&bounce_zone_tok);
1119
1120 dmat->bounce_zone = bz;
1121
1122 sysctl_ctx_init(&bz->sysctl_ctx);
1123 bz->sysctl_tree = SYSCTL_ADD_NODE(&bz->sysctl_ctx,
1124 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
1125 CTLFLAG_RD, 0, "");
1126 if (bz->sysctl_tree == NULL) {
1127 sysctl_ctx_free(&bz->sysctl_ctx);
1128 return 0; /* XXX error code? */
1129 }
1130
1131 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1132 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1133 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
1134 "Total bounce pages");
1135 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1136 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1137 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
1138 "Free bounce pages");
1139 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1140 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1141 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1142 "Reserved bounce pages");
1143 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1144 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1145 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1146 "Active bounce pages");
1147 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1148 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1149 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1150 "Total bounce requests");
1151 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1152 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1153 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1154 "Total bounce requests that were deferred");
1155 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1156 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1157 "reserve_failed", CTLFLAG_RD, &bz->reserve_failed, 0,
1158 "Total bounce page reservations that were failed");
1159 SYSCTL_ADD_STRING(&bz->sysctl_ctx,
1160 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1161 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1162 SYSCTL_ADD_INT(&bz->sysctl_ctx,
1163 SYSCTL_CHILDREN(bz->sysctl_tree), OID_AUTO,
1164 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1165
1166 return 0;
1167 }
1168
1169 static int
alloc_bounce_pages(bus_dma_tag_t dmat,u_int numpages,int flags)1170 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages, int flags)
1171 {
1172 struct bounce_zone *bz = dmat->bounce_zone;
1173 int count = 0, mflags;
1174
1175 if (flags & BUS_DMA_NOWAIT)
1176 mflags = M_NOWAIT;
1177 else
1178 mflags = M_WAITOK;
1179
1180 while (numpages > 0) {
1181 struct bounce_page *bpage;
1182
1183 bpage = kmalloc(sizeof(*bpage), M_DEVBUF, M_INTWAIT | M_ZERO);
1184
1185 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1186 mflags, 0ul,
1187 bz->lowaddr,
1188 bz->alignment, 0);
1189 if (bpage->vaddr == 0) {
1190 kfree(bpage, M_DEVBUF);
1191 break;
1192 }
1193 bpage->busaddr = pmap_kextract(bpage->vaddr);
1194
1195 BZ_LOCK(bz);
1196 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1197 total_bounce_pages++;
1198 bz->total_bpages++;
1199 bz->free_bpages++;
1200 BZ_UNLOCK(bz);
1201
1202 count++;
1203 numpages--;
1204 }
1205 return count;
1206 }
1207
1208 static void
free_bounce_pages_all(bus_dma_tag_t dmat)1209 free_bounce_pages_all(bus_dma_tag_t dmat)
1210 {
1211 struct bounce_zone *bz = dmat->bounce_zone;
1212 struct bounce_page *bpage;
1213
1214 BZ_LOCK(bz);
1215
1216 while ((bpage = STAILQ_FIRST(&bz->bounce_page_list)) != NULL) {
1217 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1218
1219 KKASSERT(total_bounce_pages > 0);
1220 total_bounce_pages--;
1221
1222 KKASSERT(bz->total_bpages > 0);
1223 bz->total_bpages--;
1224
1225 KKASSERT(bz->free_bpages > 0);
1226 bz->free_bpages--;
1227
1228 BZ_UNLOCK(bz);
1229 contigfree((void *)bpage->vaddr, PAGE_SIZE, M_DEVBUF);
1230 kfree(bpage, M_DEVBUF);
1231 BZ_LOCK(bz);
1232 }
1233 if (bz->total_bpages) {
1234 kprintf("#%d bounce pages are still in use\n",
1235 bz->total_bpages);
1236 print_backtrace(-1);
1237 }
1238
1239 BZ_UNLOCK(bz);
1240 }
1241
1242 static void
free_bounce_zone(bus_dma_tag_t dmat)1243 free_bounce_zone(bus_dma_tag_t dmat)
1244 {
1245 struct bounce_zone *bz = dmat->bounce_zone;
1246
1247 if (bz == NULL)
1248 return;
1249
1250 if ((dmat->flags & BUS_DMA_PRIVBZONE) == 0)
1251 return;
1252
1253 free_bounce_pages_all(dmat);
1254 dmat->bounce_zone = NULL;
1255
1256 if (bz->sysctl_tree != NULL)
1257 sysctl_ctx_free(&bz->sysctl_ctx);
1258 kfree(bz, M_DEVBUF);
1259 }
1260
1261 /* Assume caller holds bounce zone spinlock */
1262 static int
reserve_bounce_pages(bus_dma_tag_t dmat,bus_dmamap_t map,int commit)1263 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1264 {
1265 struct bounce_zone *bz = dmat->bounce_zone;
1266 int pages;
1267
1268 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1269 if (!commit && map->pagesneeded > (map->pagesreserved + pages)) {
1270 bz->reserve_failed++;
1271 return (map->pagesneeded - (map->pagesreserved + pages));
1272 }
1273
1274 bz->free_bpages -= pages;
1275
1276 bz->reserved_bpages += pages;
1277 KKASSERT(bz->reserved_bpages <= bz->total_bpages);
1278
1279 map->pagesreserved += pages;
1280 pages = map->pagesneeded - map->pagesreserved;
1281
1282 return pages;
1283 }
1284
1285 static void
return_bounce_pages(bus_dma_tag_t dmat,bus_dmamap_t map)1286 return_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map)
1287 {
1288 struct bounce_zone *bz = dmat->bounce_zone;
1289 int reserved = map->pagesreserved;
1290 bus_dmamap_t wait_map;
1291
1292 map->pagesreserved = 0;
1293 map->pagesneeded = 0;
1294
1295 if (reserved == 0)
1296 return;
1297
1298 BZ_LOCK(bz);
1299
1300 bz->free_bpages += reserved;
1301 KKASSERT(bz->free_bpages <= bz->total_bpages);
1302
1303 KKASSERT(bz->reserved_bpages >= reserved);
1304 bz->reserved_bpages -= reserved;
1305
1306 wait_map = get_map_waiting(dmat);
1307
1308 BZ_UNLOCK(bz);
1309
1310 if (wait_map != NULL)
1311 add_map_callback(map);
1312 }
1313
1314 static bus_addr_t
add_bounce_page(bus_dma_tag_t dmat,bus_dmamap_t map,vm_offset_t vaddr,bus_size_t * sizep)1315 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1316 bus_size_t *sizep)
1317 {
1318 struct bounce_zone *bz = dmat->bounce_zone;
1319 struct bounce_page *bpage;
1320 bus_size_t size;
1321
1322 KASSERT(map->pagesneeded > 0, ("map doesn't need any pages"));
1323 map->pagesneeded--;
1324
1325 KASSERT(map->pagesreserved > 0, ("map doesn't reserve any pages"));
1326 map->pagesreserved--;
1327
1328 BZ_LOCK(bz);
1329
1330 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1331 KASSERT(bpage != NULL, ("free page list is empty"));
1332 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1333
1334 KKASSERT(bz->reserved_bpages > 0);
1335 bz->reserved_bpages--;
1336
1337 bz->active_bpages++;
1338 KKASSERT(bz->active_bpages <= bz->total_bpages);
1339
1340 BZ_UNLOCK(bz);
1341
1342 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1343 /*
1344 * Page offset needs to be preserved. No size adjustments
1345 * needed.
1346 */
1347 bpage->vaddr |= vaddr & PAGE_MASK;
1348 bpage->busaddr |= vaddr & PAGE_MASK;
1349 size = *sizep;
1350 } else {
1351 /*
1352 * Realign to bounce page base address, reduce size if
1353 * necessary. Bounce pages are typically already
1354 * page-aligned.
1355 */
1356 size = PAGE_SIZE - (bpage->busaddr & PAGE_MASK);
1357 if (size < *sizep) {
1358 *sizep = size;
1359 } else {
1360 size = *sizep;
1361 }
1362 }
1363
1364 bpage->datavaddr = vaddr;
1365 bpage->datacount = size;
1366 STAILQ_INSERT_TAIL(&map->bpages, bpage, links);
1367 return bpage->busaddr;
1368 }
1369
1370 static void
free_bounce_page(bus_dma_tag_t dmat,struct bounce_page * bpage)1371 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1372 {
1373 struct bounce_zone *bz = dmat->bounce_zone;
1374 bus_dmamap_t map;
1375
1376 bpage->datavaddr = 0;
1377 bpage->datacount = 0;
1378
1379 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1380 /*
1381 * Reset the bounce page to start at offset 0. Other uses
1382 * of this bounce page may need to store a full page of
1383 * data and/or assume it starts on a page boundary.
1384 */
1385 bpage->vaddr &= ~PAGE_MASK;
1386 bpage->busaddr &= ~PAGE_MASK;
1387 }
1388
1389 BZ_LOCK(bz);
1390
1391 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1392
1393 bz->free_bpages++;
1394 KKASSERT(bz->free_bpages <= bz->total_bpages);
1395
1396 KKASSERT(bz->active_bpages > 0);
1397 bz->active_bpages--;
1398
1399 map = get_map_waiting(dmat);
1400
1401 BZ_UNLOCK(bz);
1402
1403 if (map != NULL && map != (void *)-1)
1404 add_map_callback(map);
1405 }
1406
1407 /* Assume caller holds bounce zone spinlock */
1408 static bus_dmamap_t
get_map_waiting(bus_dma_tag_t dmat)1409 get_map_waiting(bus_dma_tag_t dmat)
1410 {
1411 struct bounce_zone *bz = dmat->bounce_zone;
1412 bus_dmamap_t map;
1413
1414 map = STAILQ_FIRST(&bz->bounce_map_waitinglist);
1415 if (map != NULL && map != (void *)-1) {
1416 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1417 STAILQ_REMOVE_HEAD(&bz->bounce_map_waitinglist, links);
1418 bz->total_deferred++;
1419 } else {
1420 map = NULL;
1421 }
1422 }
1423 return map;
1424 }
1425
1426 static void
add_map_callback(bus_dmamap_t map)1427 add_map_callback(bus_dmamap_t map)
1428 {
1429 spin_lock(&bounce_map_list_spin);
1430 STAILQ_INSERT_TAIL(&bounce_map_callbacklist, map, links);
1431 busdma_swi_pending = 1;
1432 setsoftvm();
1433 spin_unlock(&bounce_map_list_spin);
1434 }
1435
1436 void
busdma_swi(void)1437 busdma_swi(void)
1438 {
1439 bus_dmamap_t map;
1440
1441 spin_lock(&bounce_map_list_spin);
1442 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1443 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1444 spin_unlock(&bounce_map_list_spin);
1445 bus_dmamap_load(map->dmat, map, map->buf, map->buflen,
1446 map->callback, map->callback_arg, /*flags*/0);
1447 spin_lock(&bounce_map_list_spin);
1448 }
1449 spin_unlock(&bounce_map_list_spin);
1450 }
1451
1452 int
bus_space_map(bus_space_tag_t t __unused,bus_addr_t addr,bus_size_t size,int flags __unused,bus_space_handle_t * bshp)1453 bus_space_map(bus_space_tag_t t __unused, bus_addr_t addr, bus_size_t size,
1454 int flags __unused, bus_space_handle_t *bshp)
1455 {
1456
1457 if (t == X86_64_BUS_SPACE_MEM)
1458 *bshp = (uintptr_t)pmap_mapdev(addr, size);
1459 else
1460 *bshp = addr;
1461 return (0);
1462 }
1463
1464 void
bus_space_unmap(bus_space_tag_t t,bus_space_handle_t bsh,bus_size_t size)1465 bus_space_unmap(bus_space_tag_t t, bus_space_handle_t bsh, bus_size_t size)
1466 {
1467 if (t == X86_64_BUS_SPACE_MEM)
1468 pmap_unmapdev(bsh, size);
1469 }
1470